Charge Stocking

A small exploit in the input buffering system in DmC: Devil May Cry allows the player to hold, or "stock", charged up rounds of firearms without having to hold down the Gun key. This is an especially useful ability to put your charged shots on reserve while continuing with other attacks with your hands completely free.

It can be done with both Ebony & Ivory and Revenant.

Execution
To perform the regular Charge Stock, simply choose the firearm you wish to charge, and holding the Gun key to begin charging the firearm.

During the process of charging, perform two or more different actions - perform the first action while holding the Gun key, but then release it during the animation for that first action while inputting the next action. By releasing the shoot button while performing a melee or movement technique. Additional techniques can be added on so long as they are input during the animations for previous techniques.

The second input overwrites the release of the charged shot with the new action. You'll know you've done it correctly when Dante stands idle holding the glowing firearm in his hands.

From here, you can perform any melee attacks (or Gun Special attacks, if it is a separate input key) you desire, but upon pressing the Gun key again, you'll fire the charged shot, even if you're attempting to use Ophion to lift or pull.

One of the easiest ways to stock a charge is to perform a dodge and just repeatedly jam the Dodge key while letting go of the Gun key during the single dodge.

Twosome Stock
Another form of Charge Stocking allows the player to charge both E&I and Revenant, holding their charged rounds on reserve. It  requires that Gun Special be its own  separate key, instead of a combination of the Gun and Jump keys.

To execute the Twosome Charge, arm Dante with the Revenant. Tap the Gun Special key to perform Fireworks, and during the animation for Fireworks, hold the Gun key to begin charging the shotgun.

Once Revenant is charged, stock it using the normal method detailed in the previous section. Then, switch to the pistols and stock their charge as normal as well.

The end result is Dante holding both a glowing shotgun and pistols in his hands, and having a queue in place for both charged shots. No matter what firearm you have equipped (even Kablooey) when you press the Gun key, Dante will fire Ricoshot, and upon a subsequent press will fire the Revenant Bomb shot.

This is slightly different than the basic Charge Stock, however, in that you can use Ophion to lift and pull, but in doing so you will overwrite the queued charge, so performing two or more Ophion moves will make your stocked charges disappear.

Trivia

 * The "Twosome Stock" was named by practitioners in reference to the Gunslinger skill Twosome Time
 * Charge Stocking stands alongside DMC1's Shotgun Twitching as one of the few other firearm-related exploits in the franchise